The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

Simulations show that the stars’ tug could send Mercury, Venus or Mars crashing into Earth — or let Jupiter eject our world from the solar system.

What are brown dwarfs? They’re not planets, not quite stars, but fascinating cosmic objects in their own right. Dive into the science of these “failed stars,” their role in the universe, and how they ...